Alarm and telephone system.



G. BABCOGK. ALARM AND TELEPHONE SYSTEM.

APPLIOATION IfLED DEU.2,1904. 911,565 Patented Feb. 9, 1909.

2 sums-sum 1.

Y Garmsm- EabcucbL G BABGOGK. ALARM AND TELEPHONE SYSTEM.

APPLICATION FILED 13110.2,1904. Patented Feb; 9, {SHEETS-SHEET 2.

MM 75% E D L a 4 I Mk Ur -TL To all ivhom itincy concern:

UNITED STATES IEATENT OFFICE.

Garrison BABCOCK, or ROCHESTER, NEW YORK, ASSIGNOR 'ro MERTON E. LEWIS, F" '1 v ff nocnnsrnanswronn.

ALARM AND TELEPHONE sYs'rEM.

- Be itknowntha't I, Giinnrson BAncocK,

v citihen of the"United States, residing fiat. Rochester, in the 'countyof Monroe and State of New York, have invented a certain new and useful Improvement in Alarm and Te'le hone Systems, of W'hichfthe following This 'in've'ntion relates to a combined -'1i'reis} a 1, clear, concise, and exact description, reference belng'hadto the accompanylng alarm, police signal and telephone system, and, in general, may be considered as an improvement or addition to the system explained in m United States Patent No 80 ,235, issue 'December '12, 1905. In

that patent I have explained -a'circuit wherein fire alarm signals or police signals or tele phone messages, maybe transmitted over a single c1rcu1t and indicated upon 'speclah,

ized signal-receiving a paratus .at a central office or at' a'numbero central stations, the

. transmlssion of a s ggnal or message of one e 251'nature having no e signal-recording"apparatus intended folthe indication of signals of another nature.

The addition which forms the subject matter of the present inventionl-ies principally intheprovision of a policesigna'l and. telephone equipment, whereby a policeman v -or watchman in operatingthe signal-sending ap aratu's at the variouspolicegboxes, .to

in icatethatthe'pjroper'round or beat is being made, must necessarily cause the indicate at the centralfstation-which policeorwatchman has-actuated the signal- 'sending device at appar-ticular box;

Figure 1 is a diagrammatic drawing of'the circuit "arrangements employed;v Fig. '2 is a, diagrammatic drawing of, the Policeman's 1 telephone box, the cover being removed to My invention will be understo d by refer ence to the accompanying drawing in more clearly illustrate. the interior mechan- 1 ism; Fig. 3 is a, frontelevatio'n' of the olicemans box key, the up er half of the s ell-of the key being removes;

; .tion of the key from the other sid Fig. 4 is anrelevae with'the other halfioi the shellremoved; .5 is a .centrai longitudinal section of the '-key,

taken on line 5+5-oij Fig.4; and-Fig. 6 is a detai edi w stil s-19 k for h policem n? I Specification of Letters Patent. Applicationhled December 2, 1904. .Serial no. 235,155.

drawings, forriiing apart of this specificact whatever upon the Patented Feb. 9, 1909.

- box, taken in the direction of the arrow 6 in Fig. 2.

In the drawings I have illustrated a main circuit wire 11 leading from the central sta tion S to a series of fire alarm boxes F, F,

, FF, &c., and. also to a series of police boxes,

P,"P", P, &c.

"The fire larm boxes, which need not be jspecifioally described in the present applicatlon, as their construction 18 well known to those skilled the art, provide means for interrupting the circuit in accordance with'a predetermined code, the breaks in the circuit feing of different lengths and sequence, accordingto a code employed, by means of which the signal recorded at the-central st'ation indicates which of the fire alarm boxes has been manipulated. Y Y

The main circuit leads through a main battery 12, to the central station, where a relay 14 is included in the circuit, this relay being of considerable im edance and shunted by the condenser 15.. he relay 14 controls,

by means of its armature, alocal circuit 16, including a source of current 17, andsuit'able indicating or recording 'means; 18. The relay'14' and its armature are so adjusted I that anabsolute break in the main circuit,

causin the complete cessation of the flow of curren will-causetheretraction of the arma ture to interrupt the local circuit and cause the actuation'of the signaling apparatus 18. 'A slight weakening of the current, however, due to the inclusion of a resistance in the main circuit, will not sufliciently denergize this relay to permit of the retraction of its armature. .T .e main circuit divides at 19, one path leadin through the winding 20 of the sensitive re ay 21.and thence to con: -ductor-22. The relay 21 may preferably be in the form of a volt meter movement arran ement with a contact.

The other path lea s'through' the winding 23 of the nonsensitive Morse type relay 24, and thence to the conductor 22. The main circuit is normally completed by way of theconductor 25 armature 30, which upon its retraction closes the local circuit leading from the local bat tery '31 through the code-signal-recording dev ce 3-2, to back-contact 33, armature'30,

loo

3 leading to'the contact spring 26 of a springjack 27 and thence through a normal resting *contact 28 and conductor 29. to the main of thecontacts 54 and 55. The short-circuit about the resistance 47 is not, however, broken by thisinsertion, the circuit now being traced from the sieev spring 85 through the sleeve of the plu'g to .the metal case 'of the key and thence through the break wheel 81 to the contact spring 82, to the tip 62 of the plug, and thence to the tip sprin 55. The policeman, in turning the shell 0 the key, brings the tongue 66 into engagement with projection '86 on the inside of the-case 45, this projection having an inclined upper surface, as shown. In order toturn the tongue within the box, it would be necessary to compress the spiral spring68, for'the rea-' sonthat the shou the result is that the light spiral spring 72 is overcome and the shell of the key is turned with reference to the tongue 66 and the tube 65. and bevel pinion 67 attached thereto- This turning motion continues until the pin- 8 8 extending from the edge of the pinion 67 engages a stop 89 carried uponthe' shell oi" the key.

The rotation-of the pinion 67 and the tongue 66 with reference to the shell of the key is approximately one-quarterrevolution. This turning 'motioircauses a rota- -tion of the bevel gear 69 with reference to the shell of the key, this rotation beingin the direction op osite to that indicatedby turning motionpf the tongue 66 and the en; tire shell of the ke being; simultaneous for say a quarter revo ution, when the inclined shell of the key to disengagethe bevel pinion- '67 froin-tlle teeth of the bevel gear 69.-

the arrow 73 an in such a directionthat the' pawl 76 slips over the teeth of the ratchet wheel without causing rotation of the shaft 71 and-the gear train attached thereto. At

.the time-the pin 88 engages the stop 89, and

when'also, for safetys sake} the pin 74 engages the end of its slot 7?" a turning moment is transmitted directly to the-tube '65; and the tongue 66, without the intervention of the weak spring 72. Thetongue 66 is.

turned, therefore, within" the case 45, the

upper surface of the projection-86 serves to Withdraw the tube 65 sufficiently from the Duringftheflfirst:half revolution of the key be returned to its i'iormal position by the shell the bevel gear 69 will, therefore, have been wound'upagainst thete'rision of the spring 72, and .row upon its release by thed-isen'gagemcnt of he bevel pinion 67'it will spring 72, In its rrturn, however, the'pawl .7 6 will engage the teeth pf the ratchet wheel 77 to cause the rotation of thesha'ft 71, its

gear78, the pinion, 79 and the break wheel 181. The ratio of gear is such that the break 'wheel will make one-half revolution before the pin 74' engages the forward end of the central office. I "key'has overcome the plojection 86, it is brought into contact wit der 87 engages the outside of the case at theperiphery of the key hole; The tension or p'ressureof the spring 68] being considerable, howevenand tend-ingto force the tube toward the shell of the key,-

slot 75.- In making this half revolution the spring 82 will intermittently make and breaklconne'ction with the break wheel, whereupon the resistance 47 is alternately .cut in and out of the maincircuit to produce a code signal at the central station. corresponding with the policemans'nu-mber, as will hereinafter more fully appear. The two in order that each half revolution will causethe same code signal to be produced at the After the tongue 66 of the the face 90 of the .1atch91, whereupon acontinued motion of i the key depresses the latch against the presmitter at 101, the receiver at 102 and a tele-' phone switch hook at 103 the'receiver-being supported normally by this switch hook in the: well known-manner, the weight of the receiver serving to pressthe switch hook.

downwardagainst the'upward pressure of the spring 104. The solenoid 105 serves as the, necessaiy'impedance in the transmitter circuit and also another function, which will more fully appear. Within this solenoid is halves of the break wheel are symmetrical, I

mounted a core- 106, comprising soft iron washers mounted upon an-a from which projects a downwardly extending pin 107. The corerests normally upon the contact spring 50, whose downward motionis limited by the stops 108. A catch 109 is.

uminum spindle,

pivoted upon the switch hook," as shown, this catch being subjected: to the influence .of the spriig 110 and a stoppin 111, as well 'asa stoppin'112, which limits the motion in the reverse direction. The switch book nor tact 113 connected by .conductor1114with the. sprin'gf49. At 115 I- have arranged a mally makes electrical connection with a con-Y 1' 1 0 i-detent shown in its 'norinalposition, but

which may-be moved upwardby the exercise. of suflicient pressure-against the tension of 7 the spring, 116, the detent sliding in the guide head 117-.- lfhe electrical contact 118,

normally out of contact with the switch hook i 103, makes electrical connection therewith 5 removal ofthe receiver but is agah'ulisconduring upward 'motion' thereof upon the nected therefrom when the hook has reached f its uppermost position,

The operation of the apparatus of myinvention may-be described 'asfollows;

When it is desired-to send'in a fire alarmsig;

nal a citizen manipulates one of t'he'boxes to introduce a series ofbreaks in the main I circuit, these breaks causing the'actuation of the relays 14 and 24, bu vuot of the rela 21 for -the reason that the ret action o theilto .arm 56, to contact 57, thnfiugh conductor gish or deliberate in its movement than the relay-24, which is preferably of a Morse type. There is no actuation,therefore, of the signaling apparatus controlled by the armature 30 but only of the signal receiving and recording apparatus included in the local circuit 16. I i A'policeman in sending'in thereports of his rounds inserts his hey within any of the police boxes u on the main circuit 11, and ln'turning the icy to unlock the door winds up the break mechanism, sulsequently releasing it, permitting the rotation of the break wheel to cut the resistance 47 in and out of the circuit upon the insertion of the key. The main circuit may be traced through the police box as follows: from the terminal conductor 48to the sleeve spring 185, thence to sleeve contact 63, to the shell of the policcmans l ey, throughthe break wheel 81, to contact spring $2, thence tothe tip.62 of the plug, to tip spr ng 55, to switch 58, to contact spring 49, contact spring 50, conductor 51 and conductor 52 to the ter- .minal conductor 53, which-leads again to the main circuit. Upon therelease of the winding mechanism of the lrey the connec tion between the break wheel 81 and the contact spring 82 is periodically interrupted in accordance with-the code out upon the periphery of the break wh'eel, and during these i'nternnssions the circuit 'may be traced from theterminal conductor- 48 to the resistance .47 and thence by way of the contact springs 49 and 50 to the other terminal conductor 53. The inclusion of this resistance 47 in them aim circuit causes a weahening of the normal current, thewlecrease in the current being insufficient to cause the release of the armature oi the relay 14 or'o'f the armature '38 of the relay 2%, but the decrease is sufficient to cause the partial .deenergization of the relay 21,

' whereupon the armature 30 is retracted to close 'a local circuit through the signal-recordingdevice 32. The flow of current in this local circuit causes also the flZl-SillllgOl the signallamp andut desired, the ringing of'the gong," .Thel flashing of the lamp and tli 'b"aeiuaiio ciithe signal-record- '"u'nr spends with ,the code v mg device 'nu'iiit itftaatupond M 4 ,7 iphery of the break wheel SL The central station oierator understands, however, that the ilasiing of the signal lamp 35 is not a signal for telephonic communication, and does not ordinarily insert a plug of the cord-connecting apparatusinto the springjach 27.

By the time the policeman or watchman will have turned his key suiliciently to unloclr the box, the operation of the make and break mechanism contained within his key will have been completed, and upon opcning the box a short-circuit will again have been established between the springs 85 and 55 by way of the normal connection of the break wheel 81 and the contact spring 82. The policeman thereupon depresses the lever 56 and permits its return to its normal position, whereupon the resistance 47 is intermittently cut in and out of the main circuit to cause a code signal to be recorded as liefore upon the recording instrument 32 at the central station, the codosignal sent in by the actuation of the lever SGbeing individual to the box. in this way a record is made at the central station not only of the boX numlter from which the reportis sent,

but also of the policeman sending the report, as each oliccman is provided with, a key having a iliiierent code signal upon its break wheel. I

' -i' the policeman desires to hold a telephonic communication with the central slation, he removes his receiver 102 from the switch Look, thereby permitting the upward movement of the switch hook, due to the pressure of the spring 104:. In its upward movement the'catch 109 engages the lower end of the stem 107, causing a rise of the core 106 until thecatch is tripped by the engagement of the finger 120 by the detent 115.

-Under normal conditions the current flowing through the circuit is of su'llicient strength to cause the continued upward movement of the core 106 alter having been raised to an intermediate position by the upward movement of the hook switch 103. The dctcnt 115 causes the catch to be removed from the under side of the stem or a purpose which will more fully appear. In its upward movement the core 106 causes the disconnection of the contact springs 49 and p0, which serve normally to short-circuit the telephone apparatus. The telephone circuit might be traced upon the removal of the switch hook, from the terminal-wire 18 to the sleeve spring 85 to contact 54, to tip spring 55, or from the sleeve spring 85 through the policcmans key to the tip 62 of the plug, and thence to ii p spring 55, to switch arm 56, contact 57, conductor 58, conducl or :21 and receiver 102 to terminal wire 53. A parallel path might also be traced from tl e switch arm 56 to contact 57, and thence through conductor. 122, solcnoid-l05 and transmitter 101 to the terminal wire During the upward movement of the switch hook 103 and during its electrical connection with the sliding contact 118 the transmitter 101 is short-circuimd, thereby preventing the inclusion of its resistance in the main circuit and permitting the greatest possible current to flow through the solenoid 105 to continue the upward motion of the core 106 after its disengagement by the crux-h 109: At the endof its upward travelthe receiver hook leaves the contact 18 and the transmitter will be in circuit wit u the winding 105 ready for use. The reason for this unusual mechanism in connection with the telephone circuit is that in case some other telephone at some other police box is al ready in use, it is desirable that the second policeman be-unablc to cut his telephone apparatus into the circuit. it, therefore, some other telephone is already in use, its resistance will be included in the telephone circuit, the path being similar to the normal telephone circuit previously traced, and the inclusion of this resistance in the circuit will cause a weakening of the current in the manner well understood by those skilled in the art. \v'hen, therefore, the second policeman, in attempting to cut his telephone apparatus into the circuit, removes his receiver 102 from the switch hook, the upward movement of the catch 109 carries with it the core 106 until the finger 120 is engaged by the detent 115, whereupon the catch is withdrawn from the under side of the stem 107 when the core is in an intermediate position within the solenoid 105. It will be remembered that under normal conditions, the strength of current within the solenoid is suiiicient to carry the core on up the rest of the way to the top, but on account of the weakening of the current strength, due to the inclusion of another telephone set in thecircuit, the magnetization of the solenoid 105 is not sufiicient to carry this core to the top of its stroke and upon the removal of the upward pressure exertedvby the switch hook, the core again falls to its normal position, closing the circuit between the springs 49 and 50, thereby shortcircuiting all the telephone apparatus and producing a click in the receiver 102, which the policeman may take as a signal that the line is already in use. Upon hanging t e receiver upon the switch hook, the face of the catch 109 slides upon the edge of the stem 107 ,until below. its extremity, when the s ring 110 returns it to the normal position sliown in the drawing. The attempt to connect this second telephone set in the circuit causes a slight addition to the resistance in the circuit, and this might be su posed to cause the drop of the core 100 0 the telephone set already in use, thereby cutting it out of service, but this is prevented due to the fact that the core is more, strongly attractedwhen'in itsu'opermost positlon than when in its intermediate position. The core of thefirst telephone set already in use being, therefore, in its uppermost position,

will not be dropped by a slightly-decreased l the solenoid by way of the following ath:

spring 85 and thence by way of the contact 5 1 or policemans key to the tip spring 55, thence through the switch arm 56, contact 57, conductor 58, conductor 121', contact 113, hook switch 103, conductor 51 and conductor 52 back to the terminal wire 53. closure of this short-circuit around the telephone apparatus and the solenoid 105 causes a denergization of the solenoid 105. whereupon the core 106 is dropped and returned to its normal position, whereupon the above described operations may be repeated.

The removal of any telephone receiver from its switch hook causes the inclusion of suliicient resistance in the main circuit to permit the retraction of the armature 30 of the sensitive relay 21, whereupon the local signal circuit is closed through the recording instrument .32 and the signal lamp 35. The closure of this local circuit being continuous causes the continued illumination of the lamp 35, which the operator takes as a signal fortelephone connection, and inserting a plug of the cord circuit within the jack connects the operator's telephone set' in circuit on account of the inductive relation of the windings of the repeating coil 40. The insertion of the plug serves also to shortcircuit the signaling-apparatus actuated by slight variations in the current strength in the main circuit, whereu on the telephonic voice currents may pass Tom the main circuit through the condenser 15 and conductor 130 to contact spring 44, contact spring 26, conductor 25, winding 41' of the repeatingeoil 40, and thence out on the main line circuit.

Upon the door of the box there is a connectlng clip 150 which, upon the closure of the door, connects the contacts 151 and 152, thereby short-circuiting out the helix 105 and the telephone apparatus of the substation. This insures the system against the inclusion of the resistance of this part of the circuit except when the telephone door is open and the apparatus is presumably to be put in use an it insures also the short-circuiting of the helix to permit the SOl6I10l(l.' 'l()6 to =-be drop ed, into its normal positiomwhenever the c 001' is closed.

While I have herein shown and described rslaiiid. mr iersntio th s a single; embodiment of my invention, it.

from the terminal wire 48 to the seeve The signal producing mechanism of the key, and means upon actuation ofthe key to open the box for causing operation of the signal producing mechanism to repeatedly change the main circuit condition whereby said signal receiving apparatus at the central exchange is actuated. a

9. In an alarm system, the, combination with a normally closed main circuit extending from a central exchange to'a substation, of signal receiving apparatus at the sul station, signaling apparatus at the substation contained in a box, switch mechanism for said signaling apparatus within said 1 ox, additional mechanism normally entirely disconnected and removed from said box and contained in a unitary structure, a key for said additional mechanism to actuate the lock of said box, contacts for said additional mechanism and niake-andbreak apparatus therefor, the insertion of said key within the lock causing engagement of said contacts with said switching mechanism wherel y said main circuit, is broken at said switching mechanism but simultaneously closed through the make-andbreak apparatus, and mechanism for causing operation of said inake-and-brake a aratus upon actuation of the key toopen t 1e ock whereby the condition of the main circuit is repeatedly changedto cause actuation of the signal receiving apparatus at the cen tral exchange.

10. In an alarm system, the combination with a main circuit exten'dingfrom a central exthange to a sul station, signal receiving apparatus at the central exchange, signaling apparatus at the sul station inclosedin a box, switrh mechanism for said signaling apparatus, a key for said box, a gear wheel within the body part of said key, a break wheel connected with said gear wheel, a contact extending from the body part of said key and having electrical connection with said break wheel, a contact spring for said break wheel, an additional contact extending from the body part and having electrical connection with said contact spring, a sleeve for said key extendm'g from the body dpart and having driving connection with sai gear wheel at its inner end, a

tongue extending from said sleeve,- the in-, sertion of said key within the lock" of the box causing connection of the key contacts with the switch mechanism within the "b ox whereby-the signaling apparatus is con;- nected wi said jmake-anfl reakmed? anism within the key body, and means upon motion of said key to actuate the lock to open the box for causing rotation f said gear wheel thereby causing signalingteurrent to flow through the main circuit to actuate the receiving apparatus at the central exchange.

11. In analarm system, the combination a with a main circuit extending from a central exchange to a sub station, of, signal receiving apparatus at the central exchange,.

switch mechanism and, signaling apparatus at the substation inclosed in a box, a key for said box, a gear wheel within the body part of said key, ,a driving spring for said gear wheel, a code signal break wheelgeared to said gear wheel to be driven thereby, a contact spring for engaging said break wheel, a contact plug extending from the body art, a tip contact for'said plug connected with said contact spring, a sleeve contact for said plug having electrical connection with the break wheel, a rotatable sleeve extending from the l ody portion and surrounding the plug, a pinion at the end of said sleeve for engaging said gear wheel, a key tongue extending from said sleeve, the insertion of said key within the key hole of 1 the box causing connection of the plug contacts withthe switch'mechanism wlthin the box whereby the make-and-break mechanism within the key is connectedwith the" main circuit, the rotation of the key body with respect-to the sleeve causing rotation of said gear wheel and'energization of the driving spring, and means upon further rotation ;of the key 1' ody to cause the key tongue to engage, the latch of the lock to open the box causing release of the pinion from the gear wheel where y the energized spring may,cause a reversed rotation of the gear wheel thereby actuating the make-andbreak apparatus connected with the main circuit.

12. In an alarm system, the combination with a normally closed circuit extending from a central exchange to a substation, of

signal receiving apparatus at the central exchange, signaling apparatus and circuits at the substation inclosed in a box, switch springs within said box connected with said circuits, a lock for said box, a key for said box, a gear wheel pivoted at the. interior of the body portion of the ke an energizing spring associated. with sai gear wheel, a break w heel connected with said gear wheel to be driven thereby, a contact spring for from the body portion ofthe key, a tip contact for said plug connected with said consaid break n heel, a contact plug extending tact spring, a sleeve contact for said plugjhaving electrical connection with the break wheel, a rotatable sleeve extending from the. body portion and surrounding said plug, a

Pinion secured-to the lower end of said sleeve and normally meshing with said gear Wheel, a key tongue extending from said sleeve, the insertion of the key within the key hole of the lock of the box causing connection of said plug contacts with the switch springs within the box whereby. said makeand-break mechanism within the key is connected with the main circuit, means upon rotation of the'key body with respect to the sleeve causing 'rotati'on of said pinion and gear wheel to energize said driving spring, awl and ratchet'mechanism within the key liody for preventing rotation of the break wheel upon such forward rotation of the driving wheel, the simultaneous rotation of the body and sleeve of the key causing said sleeve to be moved to withdraw the pinion from engagement with the gear wheel whereby said driving spring may. cause reverse rotation of the gear wheel, said ratchet mechanism causing rotation of the break wheel upon such reverse rotation of the gear wheel, the operation of the makeand-break mechanism causing change in the conditions of the circuit whereby the receiving apparatus at the central exchange is actuated.

13. In an alarm system, the combination with a main circuit extending from a central exchange to a substation, of signal receiving apparatus at the central exchange, switching apparatus at the substation through which said main circuit is normally continuous, a box containing said switching mechanism, a lock for said box, a key for said lock, make-and-brea-k mechanism within the body art of said key, connecting plug contacts aving connection with said make-andbreak mechanism, an actuating tongue for said key, and normally ineffective resistance inthe circuit the insertion of said key within the lock of the box causing connection of the plug contacts with said switch springs, the actuation of said key to open' said box causing operation of the make-and-break mechanism within the key whereby said resistance is repeatedly caused to be eflectivc, thereby causing flow of signaling current through the main circuit for actuatingthc receiving apparatus at the central exchange.

14. In an alarm system, the combination with a main circuit extending from a central exchange to a substation, of signal receiving apparatus at the central exchange, substation apparatus inclosed in a box and including a switch through which said main circuit is normally continuous, a key for said box, a driving gear wheel within the body part of said key, a driving spring for said driving gear, a break wheel within the body portion having connection with said driving gear, a contact spring for said break wheel, a connecting plug extending from the body portion, a tip contact for said plug connected with the contact spring, a sleeve contact for eras-cc said plug connected with the break wheel, a sleeve extending from the body portion and surrounding said plug, said sleeve being adapted for rotatable and longitudinal movement on said plug, a tongue extending from the upper end of said sleeve, a pinion secured to the'low'er end of the sleeve, a spring for normally retaining said pinion in mesh with the driving gear, the insertion of the key within the lock causing connection of the plug contacts with the switch in the box whereby said make-and-break mcchauism is included in the main circuit, the rotation of the body part relative to the sleeve causing i'orward rotation of the driving gear and cnergization of the driving spring, pawl and ratchet mechanism for preventing rotution of the break wheel upon such forward rotation of the driving gcar, means upon simultaneous rotation of the body and sleeve of the key for causing loi'igitudiual motion of said sleeve w hereby said pinion is withdrawn from driving engagement w ilh the driving gear, said pawl and ratchet mechanism causing rotation of the break wheel upon reversed rotation of the driving gear by the driving spring, the operation of said make-- and break mechanism causing repeated changes in the circuit conditions whereby the receiving apparatus in the central ex change is actuated.

15. in an alarm system, the coml'iinatiou 'ith a main circuit cxtemling from a central exchange and connected with a plurality of substations, signal receiving apparatus at the central exchange, signaling apparatus at each substation inclosed in a box, a lock for each box, said locks being similar, and keys for said locks and dillerent signal producing mechanism for each key included in a unitary structure therewith, the insertion ol any key in the lock of any of the substations causing electrical connection of the signal producing mechanism of the key with the main circuit, and the actuation oi the key to open the box causing the particular signal controlled by the signal mechanism th rein to be impressed on the main cir uit to be receive by the receiving apparatus at the central exchange.

16. In an alarm system, the cmnbination with a 'main line leading from a central exchange, of substation apparatus and circuits connected thercw ilh, a source of cur rent, the substation apparatus being inclosed in a box providedv with a lock and key mechanism, said key mechanism being normally entirely n'iechanically and electrically disconnected from the substation apparatus and box, the insertion of said key mecl anism in the lock causing electrical (,OllIlCC-llOIl thereof \iith substation apparatus and circuits, and the actuation of the key after insertion thereof causing change in the circuit conditions whereby current will ilow through the line and central exchange connected therewith.

1T In an alarm system, the-combination with a main line eading from a central 5 exchange to a substation, of signaling apparatus at the substation inclos e d in a box providedwith a lock, 'key mechanism normally electricall and mechanically disconnected from the hex" and inclosed apparatus,

1 0 circuit changing mechanism for the key mechanism adapted upon insertion of the key Within the lock to be electrically associated with the substation apparatus, the actuation of the keyimechanism to open the lock causing operation of the circuit chang ing mechanism-to change the conditions of the substation circuits and line to cause the transmission of signals to the central exchange, and. a source for providing signalmg current.

1-8. The combination with signaling apparatus, of an inclosing box therefor provided with a. look, a key for the box normally entirely. disconnected therefrom, the insertion of the key within the lock causing inclusion of the key in circuit with inclosed apparatus, and the actuation of the key to 0 en the lock causing changes in conditions of the circuits connecting the ap aratus.

u 19. The combination with signa ing apparatus, of an inclosingbox therefor provided with a lock, a key mechanism normally electrically and mechanically disconnectedfrom the box and inc-losing apparatus, circuit changing apparatus associated with the key mechanism, the insertion of the key mechanism in the lock causing continuation through the circuit changing mechanism of I circuits connecting the inclosed apparatus,

11() and the actuation of the key mechanism to open the locks causing operation of the ci-rcuit changing mechanism to change the conditions of the circuits connecting the apparatus.

20. The combination with signaling apparatus, of an inclosing box thereror provided with a lock, a key normally entirely disconnected from the box and ap aratus, the insertion of the key Within the ock causing connection thereof with the a)paratus through circuits including said *ey, the actuation of the key to open the box causing changes in the circuit conditions. 7 v

21.. The combination 'with signaling ap aratus, of an inclosing box therefor providhd with a lock and key mechanism normally entirely disconnected from the box and apparatus, a circuit connecting said apparaserially-in said circuit, the act-nation of the key mechanism to open the box causmg said circuit to be repeatedly changed.

In witness whereof, 1 have hereunto subscribed my name this 29th day of November A. 1)., 1904.

GARRISON BABCOOK. Witnesses:

C. N. QUINBY, GEO. S. MoMILLAN. 

